We had a 2008 2350 and recorded gas usage for 9,148 miles. Using 87 octane gas, driving at 60 MPH and towing a 2,700 pound car we got an overall MPG of 9.989. My guess is with no tow you might expect 1 - 1.5 more MPG's.

Most of the driving was freeway with perhaps 10-15% on primary and secondary roads. If you have any questions just drop me a private e-mail.

The Ford chassis has the same engine, transmission, and drivetrain since 2005 or 2006. The 2012 Ford chassis might weigh a few pounds more than pre-2008s but not influential.

The PC motor home portion has not changed either except slide out versus no slide out, around a 350 pound difference, again not influential.

Our fuel economy aligns with Barry-Sue's.

We tow a 4300 pound Jeep Liberty 4x4 100% of the time.We cruise at 5mph over posted speed limit with towing restrictions, but limit top speed to 70mph.Our 3 week trip from the Chicago area to the farthest point being Jasper Alberta was just under 4000 miles where we averaged 9.2mpg.We plan to slow down to improve our mpg. I would really like to hit the 10 mpg mark on vacations.We averaged 10.2 mpg not towing, taking a load full of family to a wedding 350 miles away.

It seems best fuel economy is achieved by limiting top speed to 60 mph. But that is hard to do with such a strong engine. The temptation is to go faster becasue the engine does not strain to do it. But it shows up in the mpg calculations.

Has anyone ever tried one of those so-called "performance chips" for the V-10? I have a friend who has one on his V-10 and claims he increased MPG a few notches with it.

It seems to me that performance is at one end of the sliding scale and increased MPG is at the other end. You can increase performance but you decrease MPG. You normally can not increase both without changing the engine. I sure wish you could.